Sunday, January 24, 2016

Velocity For (and By) Dummies

High-velocity
Have you ever run across someone who has clearly plucked an answer out of thin air? Who hasn't the foggiest notion what he or she is talking about? A classic example for you: an adolescent showing off his vocabulary pronounces the word "epitome" with only three syllables (rhyming it with "home") because he's only seen it in print, not heard it used (or the record, it has four syllables and rhymes with "he bit a bee"). Well, freelancers pull that particular crap a lot, and the freelancer we've caught pulling it most often, at least so far, is the one and only Joan Whetzel. We found Joan over at Hubpages.com (she's either there or eHow.com most of the time), where she misinformed her readers over the course of 661 words in a piece she called "What is Velocity."¹

What is velocity, anyway? Well anyone who bothered to look it up in the dictionary (or take a high-school physics class) would know that velocity is a vector quantity that designates both speed and direction. Joan's reword of the definition?
"Velocity, a word used frequently in scientific writing, relates to speed and motion."
We guess... not. Whetzel goes on to tell her readers that
"The fields of physics and astronomy makes use of velocity in many studies and experiments. Even sports analysis sometimes makes use of velocity, as in measuring the velocity of baseball's trajectory."
Only physics and astronomy? No other fields? and by the way, Joan, when sportscasters say "velocity," they just mean "speed": they're sportscasters, not physicists! Given that the topic is simple enough for the average middle-schooler to comprehend (Joan's lousy definition notwithstanding), it's pretty hard for her to get it wrong... but she does, like this:
  
  1. "Velocity... measures the rage of change in an object's position" Oooh! how did that object get so angry!
  2. "Velocity (v) measurements (given in meters per second or kilometers / miles per hour) are found the same way as speed measurements..." Substantially correct, but only in those units of measurement? What about cm/sec? After all, Whetzel already used the units "miles per second..." in the previous paragraph.
  3. "Constant velocity calculations measure an object moving at a constant speed in a constant direction..."  ...and they do it constantly...
  4. Humans, according to Joan, "walk at... 5kph or 1.39meters/second"; ..."jog at 10 kph or 2.7 m/s"; and "bicycle at 20 kph or 5.56 m/s." She also informs us that "cars travel at 104 kph or 5.56 m/s." Did you notice that the car's speed -- no, it's not velocity, it's a scalar quantity -- in meters per second is the same as the cyclist's? Typical Joan... 
  5. "Airplanes (specifically 7474s)..." 'Nuff said?
Sadly, HubPages (where "substandard" content is apparently invisible to the general public) still allowed this kind of abject dumbassery to stand, apparently because no one there knows the difference either. Still, we can't give HubPages the Dumbass of the Day award, so it merely goes to Ms. Whetzel. We can only hope that she gives all her colleagues a shout out at the awards ceremony...    

¹ The post has been deleted, and archive.org's Wayback machine never made a copy of the post. Oh, well, no loss...
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SI - PHYSICS

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